1xzp
From Proteopedia
(New page: 200px<br /><applet load="1xzp" size="450" color="white" frame="true" align="right" spinBox="true" caption="1xzp, resolution 2.3Å" /> '''Structure of the GTP-...) |
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| - | [[Image:1xzp.gif|left|200px]]<br /><applet load="1xzp" size=" | + | [[Image:1xzp.gif|left|200px]]<br /><applet load="1xzp" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1xzp, resolution 2.3Å" /> | caption="1xzp, resolution 2.3Å" /> | ||
'''Structure of the GTP-binding protein TrmE from Thermotoga maritima'''<br /> | '''Structure of the GTP-binding protein TrmE from Thermotoga maritima'''<br /> | ||
==Overview== | ==Overview== | ||
| - | TrmE is a 50 kDa guanine nucleotide-binding protein conserved between | + | TrmE is a 50 kDa guanine nucleotide-binding protein conserved between bacteria and man. It is involved in the modification of uridine bases (U34) at the first anticodon (wobble) position of tRNAs decoding two-family box triplets. The precise role of TrmE in the modification reaction is hitherto unknown. Here, we report the X-ray structure of TrmE from Thermotoga maritima. The structure reveals a three-domain protein comprising the N-terminal alpha/beta domain, the central helical domain and the G domain, responsible for GTP binding and hydrolysis. The N-terminal domain induces dimerization and is homologous to the tetrahydrofolate-binding domain of N,N-dimethylglycine oxidase. Biochemical and structural studies show that TrmE indeed binds formyl-tetrahydrofolate. A cysteine residue, necessary for modification of U34, is located close to the C1-group donor 5-formyl-tetrahydrofolate, suggesting a direct role of TrmE in the modification analogous to DNA modification enzymes. We propose a reaction mechanism whereby TrmE actively participates in the formylation reaction of uridine and regulates the ensuing hydrogenation reaction of a Schiff's base intermediate. |
==About this Structure== | ==About this Structure== | ||
| - | 1XZP is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Thermotoga_maritima Thermotoga maritima] with SO4 as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1XZP is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Thermotoga_maritima Thermotoga maritima] with <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1XZP OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Thermotoga maritima]] | [[Category: Thermotoga maritima]] | ||
| - | [[Category: Armengod, M | + | [[Category: Armengod, M E.]] |
[[Category: Scrima, A.]] | [[Category: Scrima, A.]] | ||
| - | [[Category: Vetter, I | + | [[Category: Vetter, I R.]] |
[[Category: Wittinghofer, A.]] | [[Category: Wittinghofer, A.]] | ||
[[Category: SO4]] | [[Category: SO4]] | ||
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[[Category: trna-modification]] | [[Category: trna-modification]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:00:21 2008'' |
Revision as of 14:00, 21 February 2008
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Structure of the GTP-binding protein TrmE from Thermotoga maritima
Overview
TrmE is a 50 kDa guanine nucleotide-binding protein conserved between bacteria and man. It is involved in the modification of uridine bases (U34) at the first anticodon (wobble) position of tRNAs decoding two-family box triplets. The precise role of TrmE in the modification reaction is hitherto unknown. Here, we report the X-ray structure of TrmE from Thermotoga maritima. The structure reveals a three-domain protein comprising the N-terminal alpha/beta domain, the central helical domain and the G domain, responsible for GTP binding and hydrolysis. The N-terminal domain induces dimerization and is homologous to the tetrahydrofolate-binding domain of N,N-dimethylglycine oxidase. Biochemical and structural studies show that TrmE indeed binds formyl-tetrahydrofolate. A cysteine residue, necessary for modification of U34, is located close to the C1-group donor 5-formyl-tetrahydrofolate, suggesting a direct role of TrmE in the modification analogous to DNA modification enzymes. We propose a reaction mechanism whereby TrmE actively participates in the formylation reaction of uridine and regulates the ensuing hydrogenation reaction of a Schiff's base intermediate.
About this Structure
1XZP is a Protein complex structure of sequences from Thermotoga maritima with as ligand. Full crystallographic information is available from OCA.
Reference
The structure of the TrmE GTP-binding protein and its implications for tRNA modification., Scrima A, Vetter IR, Armengod ME, Wittinghofer A, EMBO J. 2005 Jan 12;24(1):23-33. Epub 2004 Dec 16. PMID:15616586
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